This is the start of the FY2006 DoE Terapaths DWMI Progress Report due September 10, 2006
Current Text of Report
Today's data intensive sciences, such as High Energy Physics (HEP), need to share large amounts of data at high speeds. This in turn requires high-performance, reliable end-to-end network paths between the major collaborating sites. In addition network administrators need alerts when there are anomalous events, and grid middleware and end-users need long and short-term forecasting for application and network performance for planning, setting expectations and trouble-shooting. To enable this requires a network monitoring infrastructure between the major sites that can help notify and identify potential problems.
Active monitoring: We have developed an active network monitoring toolkit (IEPM-BW). It provides measurements, data archiving, analysis, reporting and visualization. This is now being used to make regular measurements from the following major LHC related sites: CERN, BNL, Caltech, FNAL, SLAC, and Taiwan. We also have about 60 locations worldwide that are being monitored from these important sites. We use a selection of probes based on the quality and interest in the path being measured utilizing metrics such as network routes, round trip time, one-way delays, available bandwidth and achievable throughput. We are extending the presentation of IEPM-BW by working with the USATLAS and ULTRALIGHT groups to customize reports on their most relevant interests.
To aid the detection of incorrect host settings, we have also implemented features to query the configurations of the network monitoring hosts.
As part of this we have developed and put into production, management tools for automation and robustness, including: installation and update kits; measurement and reporting of unreachable participating hosts; in-depth documentation; and a database of site, host, location, contact, OS, cpu, test parameters.
Passive Monitoring: We have studied and reported on limitations using current active end-to-end network measurement techniques in future high-speed networks. As a result of this we are exploring the effectiveness of using passive (e.g. Netflow) tools to augment or even replace some of the active measurements. In conjunction with BNL we are building a netflow monitoring toolkit using open source software to bring together quality tools to gather, store, process, analyze and visualize the performance information. The intent is to make this generally available and deploy at LHC sites such as BNL, CERN, SLAC and Michigan.
In fact, much of our development is steared by the requirements of the BNL site where we have a development version of the entire suite running.
Event Detection and Diagnosis: It is increasingly impossible for network managers to manually review thousands of reports each morning to detect problems. Thus we are developing tools to automate this activity. This includes forecasting and comparing the observed with the forecast to detect anomalous events, reporting the events, and automatically gathering information relevant to the event to assist in diagnosis. One version of the event detection is in production use. As part of this, in the last year, we have also detected, reported (together with in-depth case studies) and helped diagnose major problems at sites such as BNL, Taiwan, SDSC, NRL, BINP, and CERN. The code is still in development, we are field testing the alerts to known problems, carefully reviewing the symptoms etc. and working with network providers to understand and see what is needed to diagnose them.
High speed data transport: Our world-leaderhip role in evaluating TCP transport algorithms in production networks led Microsoft to request our help in evaluating their next generation TCP stack (CTCP). Given the extent of Windows deployment it is critical to ensure that CTCP performs well without a negative impact upon the iIternet community.
As part of this we have identified and aided the testing of numerous added features to aid the performance of the delay-based congestion control algorithm used in CTCP. Having finalized our initial report into the deployment impact of using CTCP in production environments on both long and short distance high speed Internet paths, we are know looking to publish a joint conference paper with Microsoft of our work.
Internet Measurement Confederation: An important aspect of being able to both understand and diagnose network performance problems is the unification of reporting formats and the understanding of tool performance on the Internet.
SLAC has recently started close collaboration with both Internet2 and ESnet to help develop and expand the functionalities of the international PerfSONAR collaboration.
Having had gained much momentum over the last few months due to its open-source, open-community, open-standards based ethos of network monitoring, SLAC were delighted to help contribute our network analysis skills and experience to apply the PerfSONAR technology to production systems like that of the LHC project.
We aim to apply much of our existing analysis frameworks and tools to benefit the PerfSONAR project - including that of event detection, event diagnosis.